Evolutionary Aspects of the Miogypsinidae from Azkand Formation (Oligocene-Miocene) in Kirkuk Area, Iraq

Abstract

The biometric analysis on Miogypsina from bioclastic limestone (Azkand Formation) in Kirkuk area, Iraq reveals that the evolutionary trend based on a distinct overall change in morphology of the nepiont, which change is in agreement with the principle of nepionic acceleration as defined by Tan Sin Hok,1936. The oldest species of Miogypsinoides represented by Miogypsinoides complanata and Miogypsinoides formosensis accompanied by the association Miogypsina gunteri which exhibit in the lower part of Azkand Formation of Late Oligocene age (Chattian). The early Miocene association of Miogypsina s.s. represented by Miogypsina gunteri-tani are often accompanied by Miogypsinoides. Most of these are close to Miogypsinoides bantamensis.

Benthic Foraminifera as A Tool for Indication of Microfacies, Biostratigraphy, and Depositional Environment of the Baba Formation [Late Oligocene], Kirkuk Oil Field, Northeastern Iraq

“…Several studies have been conducted in Iraq, for Oligocene -Miocene strata in Kirkuk Oil fields and High folded zones: -Buday, Ghafor, Ghafor & Muhammad, Muhammed and Ghafor, Ghafor and Ahmad, Ghafor and Najaflo, Ghafor et al,[17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. Baba Formation was described for the first time, from the Kirkuk well -10, on the Baba Dome of the Kirkuk structure, which is about 20 m thick and composed of porous dolomitized limestone, as the fore-reef equivalent of lagoonal Bajwan Formation and changes seawards into Tarjil Formation, that is from the second reef cycle of the Middle Oligocene age, this formation is covered conformably by the Bajwan Formation and underlies unconformably by the Shurau Formation.…”